A gender gap is unfolding in Iowa's Senate race, with men favoring Republican candidate and state Sen. Joni Ernst and women supporting her male opponent, Democratic U.S. Rep. Bruce Braley, a new poll shows.

According to a Quinnipiac University poll men are backing Ernst's campaign by 44 percent to 40 percent, while women back Braley by 47 percent to 36 percent.

But despite Braley's lead among women, Iowa voters said by 49 percent to 30 percent that Ernst a grandmother at 43 and a National Guard lieutenant colonel with service in Iraq, would do a better job on issues important to women

They are seeking a seat being vacated by five-term Democrat Tom Harkin, who is the first Iowa senator to voluntarily step down in 40 years.

The gender split may be as simple as routine political affiliations, said Peter Brown, assistant director of the poll.

"The unusual split is due to some degree the fact that women tend to lean Democratic while men lean Republican," Brown said in a statement.

Meanwhile, the poll showed, Ernst is edging closer to Braley as the race for the Senate heats up. She now trails Braley by 44 percent to 40 percent, compared to a 42 percent to 29 percent lead Braley had over Ernst in a March 13 Quinnipiac poll.

But when it comes to serving, voters said by 51 percent to 21 percent that Braley has the right kind of experience to be a senator, compared with 43 percent to 33 percent for Ernst.

The race is strongly divided among party lines, with Republicans backing Ernst by 79 percent to 5 percent and Democrats loyal to Braley by 89 percent to 6 percent. Independent voters are divided equally, with each candidate getting 38 percent support.

"Braley has a small lead in more measurements of personal characteristics and which candidate is better able to handle issues facing the state, but neither candidate’s views and values are firmly fixed in the electorate’s mind with a third of voters not knowing enough about either candidate to have an opinion," Brown said in the statement.

Quinnipiac surveyed 1,277 registered voters from June 12 to June 16. The poll has a margin of error of 2.7 percentage points.

A gender gap is unfolding in Iowa's Senate race, with men favoring Republican candidate and state Sen. Joni Ernst and women supporting her male opponent, Democratic U.S. Rep. Bruce Braley, a new poll shows.